Clicking IE tile in Start screen will launch IE in Modern UI (if your IE launches in desktop and want to fix to launch in Modern UI, see How to fix IE to launch in Modern UI)
Go to desktop, and launch IE.
Click gear icon at right top corner of IE window, and click “Internet Options” from menu.
In options windows, go to “Programs” tab and mark check “Open Internet Explorer tiles on the desktop”.
Now, IE will always open in desktop.
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